


Engineering a Solution

by thewinchesterlifestyle



Category: Supernatural
Genre: Alpha Castiel, Bondage, Bottom Dean, Dildos, Engineer Castiel, Fucking Machines, Knotting, Knotting Dildos, M/M, Mating Cycles/In Heat, Omega Dean, Restraints, Rough Sex, Size Kink, Top Castiel, vibrating dildo
Language: English
Status: Completed
Published: 2016-07-20
Updated: 2016-07-20
Packaged: 2018-07-24 21:06:28
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 1,885
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7523140
Author URL: https://archiveofourown.org/users/thewinchesterlifestyle/pseuds/thewinchesterlifestyle
Summary: <blockquote class="userstuff">
              <p>Engineer Castiel's poor omega has the worst heats – Castiel simply can’t keep up with him but he’s been working on a project in secret for a few months and this heat, he’s ready.</p>
            </blockquote>





	Engineering a Solution

Dean pushed his ass back against him as he sank back in another few inches. There was an indiscernible sound that escaped Dean’s mouth but Castiel was focused on dragging this knotting out. “Please Alpha.  _Oh oh Cas please I_ —”

Castiel could feel the pressure building and stopped teasing. He slammed inside, grinding against Dean’s ass and working his knot in until he’d tied his mate. The feeling of Dean locked down on him, the way his Omega’s inner muscles started to work his knot, had Castiel moaning in appreciation.

His orgasm rushed through him as his cock shot his first load into Dean. He gripped at the back of Dean’s neck and circled his hips. There was a loud moan in response as Dean shuddered, ass clamping down as his orgasm overcame him.

“Fuckin’ burnin’, Cas.” He sounded tired. It wasn’t a surprise after Dean had tossed and turned most of the night.

“I know.” Dean’s Heats always hit him hard but this time Castiel had prepared for it. His mind went to the other room and the machine he’d created specifically for Dean. He was more than confident that it would help Dean. “I’m sorry, Dean.” He massaged Dean’s neck, pressing his fingers into the muscle there to feel Dean go pliant under him.

“Do you have to leave?” it was impossible to miss the anxiety in the question. Dean didn’t turn back to look at him and instead pressed his face against the pillow in front of him.

He didn’t respond and continued to focus on Dean. They ended up on their sides while he pressed up against Dean’s ass and nuzzled against Dean’s neck. “You’re so good for me. My beautiful mate.” Castiel waited until his knot went down to press a plug inside Dean’s sloppy hole.

Dean stumbled up, into the bathroom and Castiel watched him come back to the bed.

His shower was quick when he realized the time. Castiel walked back into the bedroom, glanced over to his bed where Dean was twisted in the sheets and whimpering lowly in his sleep. Castiel released a soft sigh knowing Dean’s Heats were hard on him and that his mate was going to be seeking another knot shortly.

Castiel quickly dressed and collected the supplies he’d placed in the bottom of the closet anticipating Dean’s Heat. He walked over to the bed to carefully arrange Dean face down in the center of the bed. The restraints were padded cuffs that were attached to each of Dean’s wrists and his ankles before being secured to the bed.

He paused, fingers stroking over the red ball of the gag he’d purchased. Dean’s mouth was slack with sleep and it was easy to press the ball inside, securing it so it couldn’t be removed. Carefully he angled Dean’s head so his cheek was resting on the pillow.

It was a beautiful picture that had temptation threatening to set him off course but Castiel had important meetings with clients he was working with and he couldn’t be late. He moved away from the bed and went to the other room where the machine was set up.

Once it was in their bedroom it was only a matter of adjusting the reach and settings so when it started to fuck his mate it wouldn’t injure Dean. Castiel tugged Dean’s plug free and guided the enormous, thick vibrating dildo inside Dean’s slick hole.

He checked the position and went over the settings. His eyes moved over the fine components of the machine, checked to make sure it could sense when Dean’s Heat flared up and that his come would be pumped into Dean in the stimulation of a true knotting.

A carefully positioned camera would allow him to monitor Dean and if he noticed something off he would be able to catch it in time.

On the bed Dean shifted and a low, muffled moan escaped. Castiel immediately went to stand next to his mate, carefully running his hand over Dean’s head and offering a soft smile. “Hey.” He watched Dean twitch and took in the confused look on his mate, “I’m sorry I can’t stay during your Heat but I know how hard they are on you.” He paused as Omega gold eyes stared at him with the beginnings of another wave of Dean’s Heat. “I hate that I can’t spend every moment with you but over the past few months I’ve built something to help you.”

His hand kept moving over Dean’s head in soothing strokes while he kept his eyes locked with his mate’s.

“The machine will be able to sense when your Heat starts up and it will fuck you through it.” He could see the question in Dean’s eyes and grinned. His mate’s intelligence and curiosity was something he loved about Dean. “It will fuck you, knot you and pump you full of my seed.”

Dean moaned against his gag, eyes hooding and cheeks flushing with his Heat even as Castiel continued to explain the machine in soothing tones.

“I love you.” He pressed a kiss to Dean’s forehead, stroked his hand through Dean’s hair one more time and stepped away to turn the machine on. Castiel had designed it for Dean’s preferences and the soft whirr of it starting had him relaxing.

This Heat he would come home to a well fucked and sated in-Heat Omega. He listened to Dean whimpering against his gag and knew his mate’s Heat was already kicking up. A quick glance had him confident he’d supplied enough semen for the day and he’d stored more for the rest of the week while he was at work.

Castiel stayed to watch the machine start slowly pumping in and out of Dean’s ass before it started fucking Dean hard, exactly as he’d programed it. The muffled whimpers became louder as the machine rapidly pistoned into Dean’s slick soaked hole. It sounded wet and filthy, moving through slick and his come, while Dean strained against his binds.

Without another word he finished getting around for work and collected his things before leaving. The machine had started up without a problem and Dean wouldn’t be suffering without relief for the entire day.

Between meetings and designs Castiel checked on Dean. It was rare that he caught Dean resting and each time he turned on the video to see his mate getting fucked by the machine he couldn’t help but feel relief that his machine was doing its job and his mate wasn’t suffering on a fake knot that wouldn’t offer respite.

The way Dean’s body jerked as the massive dildo pounded him had Castiel hard each time he let himself enjoy the sight between meetings. It really did split Dean’s ass open in a truly beautiful way that he couldn’t help but enjoy.

At the end of the day Castiel didn’t find himself speeding through things. Instead he took his time, checked his messages one last time, gathered some of his work and left the office. He couldn’t wait to get home to the sweet smell of his beautiful mate.

He toed off his shoes once he got home, set his things in his office, went to grab a Gatorade and headed up the stairs. The closer he got to their bedroom the more audible Dean’s muffled moans were. Excitement raced through him as his hand curled around the knob. He pushed the door open to the sight of his invention starting to fuck Dean once more.

Castiel stepped closer, listening to the sounds of Dean moaning and whimpering into his gag, as the machine viciously pounded into him before it eventually switched into knotting mode. It caught on Dean’s hole as a normal knot would and then the machine stimulated his rough rutting in short, hard jabs.

Dean’s breathing was noticeably heavy, his cheeks were flushed and his eyes closed. The inflatable knot caught in his hole and swelled up. Castiel grinned, pleased at his success as the machine began to pump his semen into Dean.

The frenzy that had been obvious in Dean’s features lessened when Dean came and the machine was still for the duration of the knot.

Castiel loosened his tie, draped his suit jacket over a chair and walked to the bed. “I can only imagine coming home to this beautiful scene each day.” He unhooked Dean’s gag, watched Dean’s tongue darting out to lick his lips. “Here.” Castiel lifted the bottle up, grateful it was a squeeze bottle.

Dean greedily drank it, sighing when Castiel pulled the bottle back and stroked a hand through his hair. “Cas.” Dean’s voice was rough. The machine hummed lowly with a soft, muffled sound that Castiel knew was it pumping another load into Dean.

“Did it help?” he asked still running his hand through Dean’s hair.

There was a low hum from Dean and a soft sigh, “Yeah.” Castiel could see the tensing of Dean’s body as the machine did a few short little thrusts. “Thanks, Cas.”

“I’m just glad it helped. That’s all that matters.” Castiel stayed there watching his mate and occasionally checking the machine to make sure it was working until the knot deflated. Instead of pulling out the dildo remained in place in order to sense when Dean would need it but Castiel was more than happy to replace the machine with his cock.

After watching another delicious round of the machine fucking his mate’s ass wide open, of course.

Castiel stroked Dean’s hair, ran his hand down the slope of Dean’s back and rubbed against where Dean’s rim was stretched wide open around the huge dildo that continued to vibrate inside him.

A closer look revealed the puffy rim and he could see the way Dean’s inner muscles twitched around it.

Slowly he moved back to collect a chair and moved so he could have a better view of Dean’s ass getting worked over once his mate’s Heat started back up.

Now the room was filled with rough, broken moans as the dildo worked itself in and out of Dean’s plump ass in increasingly rapid thrusts. Castiel felt his cock hardening once more, arousal curling inside him, as Dean’s restraints rattled and his body could only lay there taking it over and over until the knotting feature kicked in once more.

Castiel stroked himself lazily as the machine gave several short jabs and emptied a load into Dean.

“Cas.” Dean sobbed his name as he came, shivering and panting, before going limp and laying there as the machine continued to occasionally give short, hard thrusts inside him causing the knot to rub against his prostate and tug on his rim.

Eventually the knotting finished and the machine stilled once more while the dildo continued to vibrate.

“Come on. I want you moving around, eating and drinking something.”  

He freed his mate, caught Dean when he stumbled on unsteady legs and watched Dean disappear into the bathroom. Castiel moved the machine to the corner of the room with intentions of hooking Dean up to it tomorrow.

A glance down had him deciding to use the time it took Dean to clean up to milk another knot for the machine. With an in-Heat Omega it wasn’t hard for him to knot repeatedly after all.

 


End file.
